Cover locking device for washing centrifuges



Sept. 13', 1966 G. 1. FREDHOLM 3,272,296

COVER LOCKING DEVICE FOR WASHING CENTRIFUGES Filed March 12, 1964 Figi United States Patent O 3,272,296 CGVER LGCKING DEVICE FOR WASHING CENTRIFUGES Gunnar Ivar Fredholm, Stockholm, Sweden (Forfattarvagen 44, Bromma, Sweden) Filed Mar. 12, 1964, Ser. No. 351,484 Claims priority, application Sweden, Mar. 14, 1963, 2,785/ 63 7 Claims. (Cl. 192-136) The present invention relates to an arrangement in a washing centrifuge, which is provided with an inner cover closing the centrifuge basket and operated by means of a lever.

An object of the invention is to provide means for locking of the inner cover in its closed position in the centrifuge basket before starting the centrifuge.

A further object is to provide a locking device for the inner cover in combination with a blocking member for the starting mechanism of the centrifuge.

The invention is substantially characterized in tha-t the inner cover, the lever of the cover and the driven spindle or shaft of the centrifuge basket are provided with locking members cooperating mutually and shaped and arranged in such a manner that either the inner cover and the lever or the inner cover and the said spindle can be interconnected, in which latter case the lever will be released from the inner cover.

In the drawing F IG. 1 is a vertical section through a centrifuge;

FIG. 2 is a plan view of the central part of the cover ofthe centrifuge basket;

FIG. 3 is a horizontal section taken along line 3-3 in FIG. l, and

FIG. 4 is a section taken along line 4-4 in FIG. l.

The frame of the centrifuge is designated by A and its stationary outer jacket by B. The main shaft or the spindle 1 of the centrifuge is motor driven in ka manner known per se and its centrifuge basket bottom 2 is secured to the shaft 1. The perforated ycylindrical jacket 3 of the centrifuge basket is secured at its lower end to the bottom 2 and at its upper end to a reinforcing ring 4. The outer jacket B is provided to collect the water extracted from the materials in the centrifuge basket. 'Two supports 6 are xed to the outer jacket, one beside the other and provided with coaxial bearing bolts 7, about which two parallel arms 8 are pivotally arranged. The arms support an outer cover 9, whose packing 10 rests sealingly on the upper edge 11 of the outer jacket, when the cover is in its closed position. The two arms 8 extend from the bearing bolts 7 towards the central part of the outer cover. In order to operate the outer cover the arms 8 are connected each to a pneumatically driven piston in a cylinder 12, so that the outer cover may be displaced into its closed position or out of the same by supplying compressed air to the one or the other side of the piston in cylinder 12.

A plate 13 is provided to support the materials, said plate having a central taper portion 13a which is removably placed in the centrifuge basket and rests on bottom 2, being entrained by the rotary motion of the basket.

In order to retain the materials on the plate 13 during centrifuging it is necessary to provide for an inner cover limiting the top space of the basket, which cover rotates together with the basket. The inner cover is shown at 14 and it consists of an outer reinforcing ring 15 and at a central ring 16, the rings being interconnected by means of radial stays 14. This cover framework is covered by a plate 18.

At the inside of the inner ring 16 there is fixed a at annular flange 19 which is adapted to rest on the upper Patented Sept. 13, 1966 "ice reinforced taper portion of the plate 13, when the inner cover is in its closed position. A cup-like body comprising a cylindrical jacket 20 having a bottom 21 welded thereto is inserted in the opening formed by the annular flange 19. At the upper edge of the jacket there is provided an annular flange 22 extending outwards and bearing on the annular flange 19. The cup-like body is covered with a disc 23 secured to the annular flanges 19 and 22 by means of bolts, so that the cup-like body 20, 21 forms one unit together with the inner cover 14.

A vertical shaft pivot 25 is fitted at its ends into borings in the bottom 21 and the disc 23, respectively, and extends through the cup-like body to serve as a bearing shaft of two horizontal discs 26 and 27 (FIGS. 3 and 4), which together with vertical spacers 28 form a welded unit. The said discs serve as locking means for bar-like plungers and are provided with respective keyholes 29 and 30. These holes are of the same shape but arranged in such a manner that one forms the mirror image of the other. A pin 31 is fixed to the discs 26 and 27 and extends parallel with the pivot 25. The upper portion 32 of the pin extends upwards through an arclike slot 33 in the disc 23 and constitutes an operating bar or a handle which can be externally operated and pushed from one end position of the slot 33 to the other. In the position shown in FIGS. 2-4 the narrower part of the keyhole 29 in the disc 26 is in the center and coincides with the wider part of ,the keyhole in the disc 27. A lock bolt 34 is axially ydisplaceable on the pivot 25 and the pin 31 and is acted on by springs 35 tending to displace the lock bolt towards the disc 23. A detent pin 36 arranged at the lock bolt tits into a hole 37 inthe disc 23.

The cup-like body 20 defines a locking chamber comprising locking or securing members for bar-like lock plungers which can be introduced into the chamber axially, one plunger being lixed to the main shaft 1 of the centrifuge and the other plunger being connected to a lever utilized for operating the inner cover.

The first said plunger is arranged on an upper extension 38 of the main shaft 1 and comprises portions 39, 40, the portion 39 being a neck portion having a slightly smaller diameter than the narrower part of the keyhole 30 and the portion 40 forming a bolt head having a slightly smaller diameter than the wider part of the keyhole. The other plunger is placed on a lever or arm 41 pivoting about the pivot 7 on the supports 6, the said arm at its free end being provided with a plunger 42 pivoting about a bolt 43 inserted in the arm, so that the plunger 42 may be introduced into the cuplike body 20, 21, i.e. the locking chamber, from the top through the central opening of said body. The plunger 42 has a neck portion 44, the diameter of which is slightly smaller than the narrower part of the keyhole 29. The free end portion of the plunger 42 is formed into a flat head 45, whose diameter is silghtly smaller than the wider part of the keyhole. The arm 41 carrying the plunger 42, may be raised or lowered by means of pneumatic piston cylinders 46, lthe plunger 42 being in the position shown in FIG. l when the arm 41 is lowered.

As will be seen by FIGS. 1 and 3 the narrower part of the keyhole 29 `in the disc 26 will embrace the neck portion 44 of the lock plunger 42, which in this manner is coupled with the locking chamber 20, 21 and thus with the inner cover 14. The lock bolt 34 is then in its lower position, since the ilat head 45 of the plunger 42 when pushed down into the locking chamber 20, 21 has displaced the lock bolt 34 a distance downwards from its upper position against the action of the springs 35. The detent pin 36 of the lock bolt is inactive allowing the discs 26 and 27 to swing about the pivot 2S counterclockwise from the position shown in FIGS. 3 and 4. This is effected by manually operating the handle 32, which may be pushed from the position shown in the slot 33 to the other end position of the said slot. This switching action is carried out when it is desired to withdraw the lock plunger 42 from the locking chamber, the wider opening of the keyhole 29 then embracing the plunger 42 so that its head 45 is released. Under the action of the springs 35 the plunger 43 is pushed upwards and the detent pin 36 introduced into its hole 37 in the disc 23. T he discs 26 and 27 with their keyholes are then secured in the switched-over position, in which the narrower keyhole portion of the disc 27 embraces the neck portion of the plunger 39, 40. The locking chamber 20, 21 and the inner cover 14 are thus coupled with the main shaft 1 of the centrifuge.

The plunger 42 is pushed completely out of engagement with the locking chamber by spring action on the lever 41 of the inner cover as set lforth below. The lever is operated by means of two pneumatic cylinders 46 arranged vertically in the space between the two cylinders 12, the pistons of which operate the outer cover 9. The pistons of the cylinders 46 serve during the last phase of their downward movement to compress each associated spring 47 disposed in the bottom part of the respective cylinder. When the supply of compressed air to the cylinders 46 is shut oif, the compression springs 47 bring about an angular displacement of the lever 41 of the inner cover in an upward direction when the plunger 42 is released from the locking chamber, so that the plunger 42 is lifted out of the locking chamber, the lever 41 taking the position shown by dot-dash lines 41a. The plunger 42 is mounted for pivotal movement about the pivot 43, so that it may be swung clockwise by hand through an angle of 270 to actuate an electric switching device 48, which will switch over from its off position into its on position. The switching device is connected into a circuit comprising the driving motor of the machine and a relay disposed in the conduits supplying compressed air to the operating cylinders 12. When the switch 48 is in its on position, the compressed air valves of the said cylinders will open, so that the outer cover will be lowered to its closed position. In this closed position the lever 41 bears on the inside of the lowered outer cover 9.

A summary of the operation of the device described hereinbefore will be given below.

When the centrifuge is to commence operations; the plate 13 is lowered into the centrifuge basket, filled with wet clothes. The lever 41 is locked to the inner cover 14 by means of the plunger 42 and is in a vertical position together with the outer cover 9 whereby the opening of the basket is exposed.y Compressed air is then supplied to the upper end of the cylinders 46, which bring the lever 41 downwards and the inner cover 14 into its closed position as seen in FIG. 1. All this time, the plunger 42 has been inserted and locked in the locking chamber 20, 21. After the locking chamber has been inserted into ring 19 and receives plunger 39, 40, the handle 32 is moved by hand from the position shown in FIGS. 2-4 to the other end position of the slot 33, the disc 27 then embracing the neck 39 of the plunger 39, 40 on the extension of the main shaft 1 in a locking grip while the disc 26 frees the plunger 42, which is pushed upwards by the action of spring 35. The compressed air supply to the cylinders 46 is then shut off, and the springs 47 push the lever 41 slightly upwards to lift the plunger 42 out of the locking chamber. The plunger 42 is then swung manually, which is a safety measure, through an angle of 270 clockwise and hence actuates, the switching device 48, which in its deactivated position prevents the machine from starting and the outer cover from being llowered into its closed position. When the lock plunger 42 is released from contact with the disc 26 and the lock bolt 34 displaced bythe compression action of the springs 35, the detent pin 36 is pushed into the hole 37. By these displacements of the various members, the inner cover 14 is positively secured to the extension 38 of the main shaft 1 and the inner `cover 14 is released from its arm 41.

At the same time that the switching device 48 is brought into its on position the outer cover 9` is lowered into its closed position and the machine starts.

What I claim is:

1. For a centrifuge having a main drive shaft and a basket driven by said shaft: a cover adapted for being placed on the Ibasket and coupled to the drive shaft, actuator means engageable with said cover for placing the same on the lbasket and for removing the same there from, iirst and second locking means respectively on said shaft and said actuator means, and means secured to said cover for locking the same selectively with said first and second locking means, the locking of -the latter means with one of the aforementioned said locking means releasing the other of said locking means.

2. For a centrifuge as Claimed in claim 1 wherein said means for locking the cover with said first and second locking means comprises a cup-like member defining .a chamber and having openings for passage of respective locking means, and a pair of locking members in said chamber coupled for common movement, each adapted for engaging a respective locking means when the other releases its 'associated locking means.

3. For a centrifuge as claimed in claim 2 wherein said locking members comprise two spaced parallel discs supported for pivotal movement about a common axis, said discs each having a keyhole opening for receiving the associated locking means to retain the same therein or permit release therefrom.

4. For a centrifuge as claimed in claim 3 wherein said means for locking the cover with said first and second locking means comprises a common member secured to said discs and engageable to move said discs together about said common axis.

5. For a centrifuge as claimed `in claim 3 wherein said means for locking the cover with said iirst and second locking means further comprises a lock bolt supported between said dis-cs for axial displacement, a detent on said lock bolt engageable with said cup-like member to be secured therewith and to secure the discs in an interlocked locking position, and spring means urging the lock bolt in ia direction tending to engage the detent with said cup-like member, said lock bolt being engaged with the cup-like member when the locking means on the shaft is retained with its associated disc.

6. For a centrifuge as claimed in claim 1 comprising means on said actuator means pivotably supporting the locking means associated therewith.

7. For a centrifuge as claimed in claim wherein the pivotably supported locking means is movable to a displaced position, and control means for being contacted by the latter locking means in its displaced position to deactivate the actuator means and allow activation of the drive shaft.

References Cited by the Examiner UNITED STATES PATENTS 2,907,464 10/1959 Ellis 210-146 X FOREIGN PATENTS 223,163 9/1962 Austria. 629,641 10/ 1961 Canada. 853,729 10/ 1952 Germany.

REUBEN FRIEDMAN, Primary Examiner. D. M. RIESS, Assistant Examiner. 

1. FOR A CENTRIFUGE HAVING A MAIN DRIVE SHAFT AND A BASKET DRIVEN BY SAID SHAFT: A COVER ADAPTED FOR BEING PLACED ON THE BASKET AND COUPLED TO THE DRIVE SHAFT, ACTUATOR MEANS ENGAGEABLE WITH SAID COVER FOR PLACING THE SAME ON THE BASKET AND FOR REMOVING THE SAME THERE FROM, FIRST AND SECOND LOCKING MEANS RESPECTIVELY ON SAID SHAFT AND SAID ACTUATOR MEANS, AND MEANS SECURED TO SAID COVER FOR LOCKING THE SAME SELECTIVELY WITH SAID FIRST AND SECOND LOCKING MEANS, THE LOCKING OF THE LATTER MEANS WITH ONE OF THE AFOREMENTIONED SAID LOCKING MEANS RELEASING THE OTHER OF SAID LOCKING MEANS. 